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Munc18-1 Contributes to Hippocampal Injury in Septic Rats Through Regulation of Syntanxin1A and Synaptophysin and Glutamate Levels. Neurochem Res 2023; 48:791-803. [PMID: 36335177 PMCID: PMC9638283 DOI: 10.1007/s11064-022-03806-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 10/07/2022] [Accepted: 10/20/2022] [Indexed: 11/06/2022]
Abstract
Sepsis-associated encephalopathy (SAE) is a diffuse brain dysfunction closely associated with mortality in the acute phase of sepsis. Abnormal neurotransmitters release, such as glutamate, plays a crucial role in the pathological mechanism of SAE. Munc18-1 is a key protein regulating neurotransmission. However, whether Munc18-1 plays a role in SAE by regulating glutamate transmission is still unclear. In this study, a septic rat model was established by the cecal ligation and perforation. We found an increase in the content of glutamate in the hippocampus of septic rat, the number of synaptic vesicles in the synaptic active area and the expression of the glutamate receptor NMDAR1. Meanwhile, it was found that the expressions of Munc18-1, Syntaxin1A and Synaptophysin increased, which are involved in neurotransmission. The expression levels of Syntaxin1A and Synaptophysin in hippocampus of septic rats decreased after interference using Munc18-1siRNA. We observed a decrease in the content of glutamate in the hippocampus of septic rats, the number of synaptic vesicles in the synaptic activity area and the expression of NMDAR1. Interestingly, it was also found that the down-regulation of Munc18-1 improved the vital signs of septic rats. This study shows that CLP induced the increased levels of glutamate in rat hippocampus, and Munc18-1 may participate in the process of hippocampal injury in septic rats by affecting the levels of glutamate via regulating Syntaxin1A and Synaptophysin. Munc18-1 may serve as a potential target for SAE therapy.
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Clerc R, Doll S, Riou LM, Perret P, Broisat A, Soubies A, Desruet MD, Fagret D, Schwebel C, Ghezzi C. Sympathetic cardiac function in early sepsis: Noninvasive evaluation with [ 123I]-meta-iodobenzylguanidine ( 123I-MIBG) in vivo SPECT imaging. J Nucl Cardiol 2018; 25:483-491. [PMID: 27572925 DOI: 10.1007/s12350-016-0619-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 07/07/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND Sympathetic system abnormalities have been reported in sepsis-related cardiac dysfunction. The present study aimed at evaluating the potential of the norepinephrine radiolabeled analogue [123I]-meta-iodobenzylguanidine (123I-MIBG) for the noninvasive assessment of modifications in cardiac sympathetic activity occurring in lipopolysaccharide (LPS)-induced experimental acute sepsis by single-photon emission computed tomographic imaging (SPECT). METHODS AND RESULTS Sepsis was induced in male Wistar rats by intraperitoneal injection of 10 mg·kg-1 lipopolysaccharide (n = 16), whereas control animals (n = 7) were injected with vehicle (NaCl 0.9%). Echocardiography in LPS-injected animals (n = 8) demonstrated systolic and diastolic cardiac dysfunction. 123I-MIBG was injected 1 hour after LPS or vehicle administration (n = 8 and 7, respectively), and in vivo SPECT imaging was performed early and late (20 and 180 minutes) after tracer injection prior to animal euthanasia and ex vivo assessment of 123I-MIBG biodistribution. Global and 17-segment SPECT image analysis indicated that early 123I-MIBG activity was not affected by LPS treatment, whereas late cardiac tracer activity was significantly decreased in LPS-treated animals. Consequently, the cardiac washout of 123I-MIBG was significantly higher in LPS-treated (63.3% ± 4.0%) than that in control animals (56.7% ± 5.8%) (P < .05). CONCLUSION Sepsis-induced modifications in cardiac sympathetic nervous system activity were evidenced by noninvasive in vivo 123I-MIBG SPECT imaging.
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Affiliation(s)
- Romain Clerc
- INSERM U1039, Radiopharmaceutiques Biocliniques, Grenoble, France
- Université Grenoble Alpes, Grenoble, France
| | - Sophia Doll
- INSERM U1039, Radiopharmaceutiques Biocliniques, Grenoble, France
- Université Grenoble Alpes, Grenoble, France
| | - Laurent M Riou
- INSERM U1039, Radiopharmaceutiques Biocliniques, Grenoble, France.
- Université Grenoble Alpes, Grenoble, France.
- INSERM U1039, Faculté de Médecine de Grenoble, 38700, La Tronche, France.
| | - Pascale Perret
- INSERM U1039, Radiopharmaceutiques Biocliniques, Grenoble, France
- Université Grenoble Alpes, Grenoble, France
| | - Alexis Broisat
- INSERM U1039, Radiopharmaceutiques Biocliniques, Grenoble, France
- Université Grenoble Alpes, Grenoble, France
| | - Audrey Soubies
- INSERM U1039, Radiopharmaceutiques Biocliniques, Grenoble, France
- Université Grenoble Alpes, Grenoble, France
| | - Marie-Dominique Desruet
- INSERM U1039, Radiopharmaceutiques Biocliniques, Grenoble, France
- Nuclear Medicine Department, Grenoble University Hospital, Grenoble, France
| | - Daniel Fagret
- INSERM U1039, Radiopharmaceutiques Biocliniques, Grenoble, France
- Nuclear Medicine Department, Grenoble University Hospital, Grenoble, France
| | - Carole Schwebel
- INSERM U1039, Radiopharmaceutiques Biocliniques, Grenoble, France
- Université Grenoble Alpes, Grenoble, France
- Intensive Care Unit, Grenoble University Hospital, Grenoble, France
| | - Catherine Ghezzi
- INSERM U1039, Radiopharmaceutiques Biocliniques, Grenoble, France
- Université Grenoble Alpes, Grenoble, France
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Xu X, Sun B. Platelet granule secretion mechanisms: Are they modified in sepsis? Thromb Res 2015; 136:845-50. [DOI: 10.1016/j.thromres.2015.09.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 08/19/2015] [Accepted: 09/06/2015] [Indexed: 12/31/2022]
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